原标题：ADI SSM2603立体声数字音频CODEC方案

　　ADI公司的SSM2603是低功耗高质量立体声数字音频CODEC,具有一组立体声可编程增益放大器(PGA)线输入和麦克风输入.SSM2603具有两个24位ADC通路和两个24位DAC通路,可工作在主/从.3.3V时,DAC SNR为100dB(A加权),48kHz的THD为-80dB; ADC SNR为90dB(A加权), 48kHz的THD为-80dB.主要用在手机,MP3播放器,手提游戏机,教育玩具和手提电子设备.本文介绍SSM2603主要特性, 功能方框图，典型应用电路图和SSM2603评估板主要特性,详细电路图和材料清单(BOM).

　　The SSM2603 is a low power, high quality stereo audio codec for portable digital audio applications with one set of stereo programmable gain amplifier (PGA) line inputs and one monaural microphone input. It features two 24-bit analog-to- digital converter (ADC) channels and two 24-bit digital-to- analog (DAC) converter channels. The SSM2603 can operate as a master or a slave. It supports various master clock frequencies, including 12 MHz or 24 MHz for USB devices; standard 256 fS or 384 fS based rates, such as 12.288 MHz and 24.576 MHz; and many common audio sampling rates, such as 96 kHz, 88.2 kHz, 48 kHz, 44.1 kHz, 32 kHz, 24 kHz, 22.05 kHz, 16 kHz, 12 kHz, 11.025 kHz, and 8 kHz. The SSM2603 can operate at power supplies as low as 1.8 V for the analog circuitry and as low as 1.5 V for the digital circuitry. The maximum voltage supply is 3.6 V for all supplies. The SSM2603 software-programmable stereo output options provide the user with many application possibilities. Its volume control functions provide a large range of gain control of the audio signal. The SSM2603 is specified over the industrial temperature range of −40℃ to +85℃. It is available in a 28-lead, 5 mm × 5 mm lead frame chip scale package (LFCSP).

　　SSM2603主要特性:

　　Stereo, 24-bit analog-to-digital and digital-to-analog converters

　　DAC SNR: 100 dB (A-weighted), THD: −80 dB at 48 kHz, 3.3 V

　　ADC SNR: 90 dB (A-weighted), THD: −80 dB at 48 kHz, 3.3 V

　　Highly efficient headphone amplifier

　　Stereo line input and monaural microphone input

　　Low power

　　7 mW stereo playback (1.8 V/1.5 V supplies)

　　14 mW record and playback (1.8 V/1.5 V supplies)

　　Low supply voltages

　　Analog: 1.8 V to 3.6 V

　　Digital core: 1.5 V to 3.6 V

　　Digital I/O: 1.8 V to 3.6 V

　　256/384 oversampling rate in normal mode; 250/272 over- sampling rate in USB mode

　　Audio sampling rates: 8 kHz, 11.025 kHz, 12 kHz, 16 kHz, 22.05 kHz, 24 kHz, 32 kHz, 44.1 kHz, 48 kHz, 88.2 kHz, and 96 kHz

　　28-lead, 5 mm×5 mm LFCSP (QFN) package

　　SSM2603应用:

　　Mobile phones

　　MP3 players

　　Portable gaming

　　Portable electronics

　　Educational toys

　　图1.SSM2603功能方框图

　　图2.SSM2603功率管理功能定位方框图(控制寄存器R6,位D0到位D7)

　　图2.SSM2603典型应用电路图

　　SSM2603评估板

　　The SSM2603 evaluation board carries a complete application circuit for the SSM2603. The board features a USB connection to a host PC. This serves as the power supply, digital audio data, and control/status data link, making it a plug-and-play USB audio device that can communicate with the software under the Microsoft® Windows® operating system. The board also has a general-purpose 2.54 mm pitch connector to connect to an external DSP/MCU for digital audio signals.

　　SSM2603评估板主要特性:

　　USB connectivity to host PC

　　External connectivity to DSP/MCU for digital audio signals (available through general-purpose 2.54 mm pitch connector)

　　4 audio jacks: stereo line input, mono microphone input, stereo line output, and stereo headphone output

　　Multiple test points across the board for monitoring signals

　　Master/slave mode selectivity

　　图3.SSM2603评估板顶外形图

　　图3.SSM2603评估板电路图(1)

　　图3.SSM2603评估板电路图(电源)

　　图4.SSM2603评估板电路图(数字缓冲器)

　　图5.SSM2603评估板电路图(模拟输出)

　　图5.SSM2603评估板电路图(模拟输入)

　　图5.SSM2603评估板电路图(USB,MCU)

　　材料清单(BOM):